I have a 6500 frame (new warranty replacement) with a Psylo shock and it works great. I've put XTR shift/brake levers, Avid Mag brakes, Easton bars and post, Titec stem, etc.
Basically, I am trying to replace everything at some point due to wear. I've ridden the S**t out of the bike and it works great. I got the frame replaced ( the old style frame had a crack that couldn't be seen) and couldn't be happier with it.